EBML header parsing failed

[Kreyren]

$ ~/.local/bin/gifter ~/Pictures/reactions/true-startrek-nerd.webm outpit.gif 480 10
[matroska,webm @ 0x2384880] Format matroska,webm detected only with low score of 1, misdetection possible!
Truncating packet of size 3907 to 1312
[matroska,webm @ 0x2384880] EBML header parsing failed
/home/kreyren/Pictures/reactions/true-startrek-nerd.webm: Invalid data found when processing input
[matroska,webm @ 0xd3c9c0] Format matroska,webm detected only with low score of 1, misdetection possible!
Truncating packet of size 3907 to 1312
[matroska,webm @ 0xd3c9c0] EBML header parsing failed
/home/kreyren/Pictures/reactions/true-startrek-nerd.webm: Invalid data found when processing input
$ cat ~/.local/bin/gifter
#!/bin/sh
# https://github.com/thevangelist/FFMPEG-gif-script-for-bash/blob/master/gifenc.sh

if test $# -lt 4; then 
	cat <<-EOH
	$0: Script to generate animated gifs easily from command line.
	
	Usage:
	
	$0 input.(mp4|avi|webm|flv|...) output.gif horizontal_resolution fps
	EOH
    exit 1
fi

palette="$(mktemp /tmp/ffmpeg2gifXXXXXX.png)"

filters="fps=$4,scale=$3:-1:flags=lanczos"

ffmpeg -v warning -i "$1" -vf "$filters,palettegen" -y "$palette"
ffmpeg -v warning -i "$1" -i $palette -lavfi "$filters [x]; [x][1:v] paletteuse" -y "$2"

rm -f "$palette"

CC @thevangelist